New submission from Alex Gaynor: Following the length_hint PEP, we should expose this facility to end-python programmers. The semantics would be basically: the list has behavior identical to if you hadn't provided length_hint, except the VM is free to preallocate efficiently.
CPython (and PyPy) use this kind of logic internally all over the place when lists are to be returned (including, but not limited to, list() with a single argument!) If this is considered to be a good idea I'll whip up a patch. ---------- messages: 183332 nosy: alex priority: normal severity: normal status: open title: Add length_hint parameter to list, dict, set constructors to allow efficient presizing type: performance versions: Python 3.4 _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue17338> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
